Upright vacuum cleaners are well known in the art. Upright vacuum cleaners generally include a nozzle assembly equipped with wheels that allows the nozzle assembly to be rolled across the floor being cleaned. The nozzle assembly includes a suction inlet and more often than not is incorporated with a rotary agitator that sweeps dirt and debris from the nap of an underlying carpet being cleaned.
A handle assembly is pivotally connected to the nozzle assembly. Typically, a dirt collection vessel in the form of a vacuum cleaner bag or a dirt cup is carried on the nozzle assembly. A suction generator is also provided to produce a negative air stream that draws dirt and debris into the vacuum cleaner. The dirt and debris is captured in the dirt collection vessel and clean air is exhausted back into the environment. The suction generator may be carried either on the handle assembly or the nozzle assembly.
During floor cleaning operation, the handle assembly is tilted with respect to the nozzle assembly at oblique angles. Thus, the handle assembly is inclined to allow the operator to guide the vacuum cleaner to and fro across the floor. Periodically the operator may need to release the handle in order to move a piece of small furniture or other object to allow cleaning. At this time the operator typically pushes the handle forward into the upright or storage position. If the rotary agitator of the vacuum cleaner remains activated, the projecting bristle tufts of a rotary agitator will continually engage an underlying carpet at a single point potentially creating unnecessary carpet wear. In order to address this problem some upright vacuum cleaners have been equipped with an agitator lift feature whereby the nozzle assembly and the rotary agitator connected thereto are lifted away from the floor so that the bristle tufts do not engage and create carpet wear while the vacuum cleaner remains stationary with the handle in the upright storage position. Examples of prior art agitator lift features may be found in, for example, U.S. Pat. Nos. 3,579,699; 5,269,042; 5,551,120; and 5,974,625.
This document describes a new and improved agitator lift feature for an upright vacuum cleaner that is of simple and inexpensive construction and that provides very efficient and effective operation.